Self-aligned silicon carbide semiconductor devices

Abstract

A self-aligned silicon carbide power MESFET with improved current stability and a method of making the device are described. The device, which includes raised source and drain regions separated by a gate recess, has improved current stability as a result of reduced surface trapping effects even at low gate biases. The device can be made using a self-aligned process in which a substrate comprising an n+-doped SiC layer on an n-doped SiC channel layer is etched to define raised source and drain regions (e.g., raised fingers) using a metal etch mask. The metal etch mask is then annealed to form source and drain ohmic contacts. A single- or multilayer dielectric film is then grown or deposited and anisotropically etched. A Schottky contact layer and a final metal layer are subsequently deposited using evaporation or another anisotropic deposition technique followed by an optional isotropic etch of dielectric layer or layers.

Description

[0001] This application claims priority to US Provisional Patent Application Serial No. 60 / 552,398, filed March 12,2004. The entire content of this provisional application is incorporated by reference. technical field [0002] The present application relates generally to semiconductor devices, and more particularly, to self-aligned silicon carbide power MESFETs and methods of fabrication thereof. Background technique [0003] Silicon carbide metal-semiconductor field-effect transistors (also known as MESFETs) have been greatly appreciated by researchers as ideal devices for high-power continuous-wave (CW) high-frequency (S and X-band) linear broadband monolithic microwave integrated circuits (MMICs). focus on. [1] [0004] In the past decade, the development of power SiC MESFET devices has achieved great success. However, some questions about these devices remain unresolved. In particular, one of the main problems hindering the widespread commercialization of power SiCME...

AI Technical Summary

Problems solved by technology

However, some questions about these devices remain unresolved

In particular, one of the major issues hindering the widespread commercialization of power SiCMESFET devices is the current instability due to the trapping effect

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